top is a Unix/Linux/BSD program to show what processing are running. It can show the top users of CPU or memory.
Questions tagged [top]
294 questions
557
votes
3 answers
What exactly do the colors in htop status bars mean?
By default, htop shows colored status bars for processors, memory, and swap. From left to right, the bars are colored green, blue, yellow, and red depending on some thresholds.
What does it mean when the Memory bar has a small level of green and…

tobym
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What does Virtual memory size in top mean?
I am running top to monitor my server performance and 2 of my java processes show virtual memory of up to 800MB-1GB. Is that a bad thing?
What does virtual memory mean?
And oh btw, I have swap of 1GB and it shows 0% used. So I am confused.
Java…

kapso
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6 answers
Show full process name in top
I'm running a Rails stack on Ubuntu.
When I call ps -AF, I get a descriptive process name set by the Apache module like
00:00:43 Rails: /var/www...
which is really helpful in diagnosing load issues.
But when I call top, the same process shows up…

Ben K.
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Why does htop have three load averages?
On htop, it shows three load averages, one bold, one normal, one red. What do they signify?

chrism2671
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How to understand the memory usage and load average in linux server
I am using a linux server which has 128GB of memory and 24 cores. I use top to see how much it is used. Its output is pasted at the end of the post. Here are two questions:
(1) I see that each of the running processes occupies a very small…

Tim
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Linux - How can I see what's waiting for disk IO
I have a server that has a really high load. Nothing is jumping out at me in terms of CPU usage, and it's not swapping.
I think it's cause some processes are waiting for disk IO, and I want to see what's waiting.
Is there any programme that'll show…

Amandasaurus
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wa (Waiting for I/O) from top command is big
I have a forum with a lot of visitors, Some days the load increase to reach 40 without increase of the number vistors. As you can see from the below output, the waiting time is high (57%). how do I find the reason for that?
The server software is…

usef_ksa
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How to get top command output to show rake arguments?
In the past, all of our servers have automatically shown command arguments passed to rake when we view them in top. For example:
But on this particular server, we get this instead (picture is top running, showing the rake command, but not showing…

wbharding
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What does %st mean in top?
Here is an example from my top:
Cpu(s): 6.0%us, 3.0%sy, 0.0%ni, 78.7%id, 0.0%wa, 0.0%hi, 0.3%si, 12.0%st
I am trying to figure out the significance of the %st field. I read that it means steal cpu and it represents time spent by the…

Ben
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How to interpret output from Linux 'top' command?
Following a discussion made HERE about how PHP-FPM consuming memory, I just found a problem in reading the memory in top command. Here is a screenshot of my top just after restarting PHP-FPM. Everything is normal: about 20 PHP-FPM processes, each…

Googlebot
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Memory Usage Numbers In top/htop
Can someone please explain this top output. Each PHP process is using 30% of the total memory or of the used memory? Furthermore how can it be that the combined used memory across all the PHP processes far exceeds my system memory? Is this the…

Mem
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Find out what high CPU usage apache process is actually doing?
Currently having a few issues with our server where, intermittently, we seem to get apache processes which just run and run, taking up 100% CPU.
When running top, we see the following:
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ …

BT643
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How is memory usage reported in Linux?
Using ps, I can see the size, the vsize (same as top's VIRT?), and the rss (same as top's RES?). (One more I see in top is SHR.)
Could someone summarize for me what these different fields mean?

Jim Hunziker
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How to have linux top command show memory summary in megabytes not kilobytes
Redhat EL5
I had my top configured the just the way I like showing the memory summary and swap summary in MB. I had to close my shell and then when I re-opened it, it is back showing in (default ?) kilobytes.
I have scoured google, and top help and…

Michael Irey
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10 GB of RAM unaccounted for by top
Here's my free and smem output:
danslimmon@bad-server:~$ free -m
total used free shared buffers cached
Mem: 30147 29928 218 6 4 3086
-/+ buffers/cache: 26837 …

danslimmon
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